Optical Angular Momentum最新文献_第7页

Automatic road edge detection from Mobile Laser Scanning (MLS) 移动激光扫描(MLS)自动道路边缘检测

Optical Angular Momentum Pub Date : 2016-11-11 DOI: 10.1117/12.2257108

Carlos Cabo, S. Garcia-Cortes, A. Menéndez-Díaz, C. Ordóñez

引用次数: 1

Multi-wavelength digital holography for shape measurement of grinded surfaces with ultimate accuracy 用于磨削表面形状测量的多波长数字全息技术，具有极高的精度

Optical Angular Momentum Pub Date : 2016-11-11 DOI: 10.1117/12.2256665

P. Psota, V. Ledl, P. Vojtíšek, T. Vít

{"title":"Multi-wavelength digital holography for shape measurement of grinded surfaces with ultimate accuracy","authors":"P. Psota, V. Ledl, P. Vojtíšek, T. Vít","doi":"10.1117/12.2256665","DOIUrl":"https://doi.org/10.1117/12.2256665","url":null,"abstract":"The entry of CNC machining processes into optics brought the possibility of nearly arbitrary shape generation. Obviously the measurement of the generated shape increasingly gains the importance, because the generation has to be performed in an iterative manner as the required precision increases. Often mid spatial frequency error is neglected because it is not an easy task to be measured. Unfortunately those unwanted residual deviation in a shape left after grinding could dramatically complicate a subsequent polishing procedure. Mid spatial frequency content if not controlled well could spoils significantly the performance of the optical system. Elimination of mid spatial residuals originated in grinding process is nearly impossible or very difficult by sub-aperture polishing. Hence it is important to measure the grinded surface with sufficient lateral resolution. Tactile probes (usually used for shape measurement of grinded surfaces) can measure with sufficient lateral resolution but only at the expense of time. Interferometer based techniques fail when applied to scattering surfaces due to speckles. The authors have proposed multi-wavelength multi-directional digital holography – the method perfectly suitable for grinded surfaces shape measurement. Naturally, reconstructed phase maps are affected by speckle noise implying significant errors in the calculation of the shape of the surface. In order to reduce the effect of speckle noise and hence to increase the sensitivity of the measurement of the grinded surface shape, we propose to apply windowed digital holography. This paper describes the principle of the windowed digital holography and the way of straightforward application of the method in shape measurement of grinded surfaces.","PeriodicalId":112965,"journal":{"name":"Optical Angular Momentum","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124080674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Imaging in laser spectroscopy by a single-pixel camera based on speckle patterns 基于散斑模式的单像素相机在激光光谱学中的成像

Optical Angular Momentum Pub Date : 2016-11-11 DOI: 10.1117/12.2256988

K. Žídek, J. Václavík

{"title":"Imaging in laser spectroscopy by a single-pixel camera based on speckle patterns","authors":"K. Žídek, J. Václavík","doi":"10.1117/12.2256988","DOIUrl":"https://doi.org/10.1117/12.2256988","url":null,"abstract":"Compressed sensing (CS) is a branch of computational optics able to reconstruct an image (or any other information) from a reduced number of measurements – thus significantly saving measurement time. It relies on encoding the detected information by a random pattern and consequent mathematical reconstruction. CS can be the enabling step to carry out imaging in many time-consuming measurements. The critical step in CS experiments is the method to invoke encoding by a random mask. Complex devices and relay optics are commonly used for the purpose. We present a new approach of creating the random mask by using laser speckles from coherent laser light passing through a diffusor. This concept is especially powerful in laser spectroscopy, where it does not require any complicated modification of the current techniques. The main advantage consist in the unmatched simplicity of the random pattern generation and a versatility of the pattern resolution. Unlike in the case of commonly used random masks, here the pattern fineness can be adjusted by changing the laser spot size being diffused. We demonstrate the pattern tuning together with the connected changes in the pattern statistics. In particular, the issue of patterns orthogonality, which is important for the CS applications, is discussed. Finally, we demonstrate on a set of 200 acquired speckle patterns that the concept can be successfully employed for single-pixel camera imaging. We discuss requirements on detector noise for the image reconstruction.","PeriodicalId":112965,"journal":{"name":"Optical Angular Momentum","volume":"10151 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129147406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Monitoring of overmodulation effect in high efficient generally slanted transmission gratings produced in photopolymers 光聚合物中高效一般斜透射光栅过调制效应的监测

Optical Angular Momentum Pub Date : 2016-11-11 DOI: 10.1117/12.2256488

P. Vojtíšek, M. Květoň, I. Richter

{"title":"Monitoring of overmodulation effect in high efficient generally slanted transmission gratings produced in photopolymers","authors":"P. Vojtíšek, M. Květoň, I. Richter","doi":"10.1117/12.2256488","DOIUrl":"https://doi.org/10.1117/12.2256488","url":null,"abstract":"In our laboratory, we use for fabrication of volume phase diffraction gratings a photopolymer recording material Bayfol HX. It is an extremely effective recording material; a high value of the refractive index modulation is obtained already during a holographic exposure. The value of this refractive index modulation influences the diffraction properties (e.g. efficiency) of the recorded gratings and, in the case of transmission gratings, the growth of this modulation beyond the optimal value leads to an effect of so called overmodulation. This effect is, in the most cases, unwanted as it causes the decrease of the diffraction efficiency from its maximum value (practically close to 100%). The analysis whether the grating is over- or under- modulated is relatively difficult as the value of the refractive index modulation can’t be measured directly and it is evaluated from the measurement of the diffraction efficiency. However, the obtained value can be often incorrect due to the overmodulation effect. In this contribution, we would like to extend (to include any arbitrary slanted transmission gratings) and discuss a simple measurement method for the determination of the correct value of the refractive index modulation based on a multiple/two-wavelength measurement of a diffraction efficiency of transmission gratings. The theoretical idea of this method and also experimental results obtained on photopolymer Bayfol HX will be presented. From practical point of view, this approach help us mainly for correct adjustment of exposure parameters to reach efficient gratings.","PeriodicalId":112965,"journal":{"name":"Optical Angular Momentum","volume":"10151 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129727376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Influence of oxygen on the quality of the PZT thin films prepared by IBS 氧对IBS法制备PZT薄膜质量的影响

Optical Angular Momentum Pub Date : 2016-11-11 DOI: 10.1117/12.2257224

P. Horodyska, J. Hlubuček, K. Žídek, J. Václavík

引用次数: 0

Positioning system and lattice design for subaperture stitching interferometry 子孔径拼接干涉测量定位系统及点阵设计

Optical Angular Momentum Pub Date : 2016-11-11 DOI: 10.1117/12.2257310

J. Kredba, P. Psota

引用次数: 1

Absolute and relative surface profile interferometry using multiple frequency-scanned lasers 使用多频扫描激光的绝对和相对表面轮廓干涉测量

Optical Angular Momentum Pub Date : 2016-10-24 DOI: 10.1117/12.2263656

M. Peca, P. Psota, P. Vojtíšek, V. Ledl

引用次数: 2